Many questions obviously surround his death and one of the major issues that will need to be addressed is how the Fox series moves on without one of its marquee stars. Monteith is hardly the first star to die while his TV series was still running, though. While it doesn't happen often, it has occurred, leaving producers to try and figure out how to proceed. Here’s a look at some examples:

‘Cheers’

Nicholas Colasanto played the beloved and dim-witted Coach on the NBC series before he was felled by a heart attack in 1985 after three seasons on the air. Woody Harrelson stepped in brilliantly as his replacement for the remained of the hugely successful sitcom’s run.

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‘The Sopranos’

Nancy Marchand played the mother of James Gandolfini’s Tony and died between seasons two and three in 2000. She was an essential character and her passing was addressed by also having her character die.

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‘NewsRadio’

Phil Hartman tragically died in a murder/suicide involving his wife in 1998, leaving a huge void on this NBC series. He was replaced by Jon Lovitz, who remained on the show for the program’s fifth and final season.

NBC

‘8 Simple Rules’

John Ritter died from an undetected heart issue during a taping of the show in 2003 during '8 Simple Rules'' second season. The show went on a brief hiatus, but returned with Ritter's character dying on the show. The show finished the season and went on for one more, with David Spade and James Garner stepping as series regulars.

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‘The Royal Family’

Redd Foxx was a comedy icon looking to return to small screen greatness with this CBS vehicle, co-starring Della Reese. The show debuted to stellar ratings in 1991, but the success was all too brief – Foxx died of a heart attack and the series was canceled.

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‘Suddenly Susan’

This NBC comedy enjoyed moderate success, but was struck by the suicide of David Strickland in 1999. The show addressed his passing with a tribute episode in the third season finale. The series wound up lasting one more year, with a revamped writing staff and several other casting changes.

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‘The Beast’

Patrick Swayze starred for one season on this gritty A&E drama, which ran for one season in 2009. The plug was pulled on the show in June of that year because of Swayze’s battle with pancreatic cancer, which he ultimately died from in September of that year.

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‘Chico and the Man’

Breakout comedian Freddie Prinze died from a self-inflicted gunshot during the sitcom’s third season in 1977. Eventually, viewers learned his character had died and the show made it through one more season.

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‘Spartacus’

Star Andy Whitfield, who played the title role on Starz’s ‘Spartacus: War of the Damned,’ died from non-Hodgkin lymphoma in 2011. After initially beating the disease, he suffered a recurrence and the title role for the six-part prequel ‘Spartacus: Gods of the Arena’ had to be recast.

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‘Dallas’

Jim Davis starred as Jock Ewing on the enormously successful soap opera ‘Dallas’ when he died of cancer during the show’s fourth season. Producers nixed the idea of casting another actor in the role and eventually the show killed off his character during the fifth season. The series itself lasted another nine seasons.

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‘Dallas’ (TNT)

The ‘Dallas’ universe suffered another death during the show’s reboot on TNT. Hagman, who played the iconic J.R. Ewing on the original series, reprised the role, but died from leukemia in 2012 between the first and second season. His character died in the middle of season two. Earlier this year, TNT renewed the drama for another season.